Tensioning device



Oct. 21 1924.

l W.'D. HITCIQI ET AL TENSIONING DEVICE Filed July '2. 192s 2 Sheets-Shes,u l

.iff

' W. D. HITCH ET AL.

TENsIoNING DEVICE Filed July 7.. 1923:` 2 Shee'ts-Shee.. 2

Patented Oct. 21, 1924.

U NIT L;

WALTER D. HITCH AND OSCAR It. GRAF, OF NEW ALBANY, INDIANA.

TENSIONING DEVICE.

Appliation tiled July 7,

To all lwhom t may concern.'

Be it known that WALTER D. Hrrorr and OSCAR R. GRAF, citizens of the United States, residing at New Albany, in the county of Floyd and State of Indiana, have invented certain new and useful Improvements in Tensioning Devices, of which the following is a specification.

This invention relates to tensioning devices and more particularly to a device for tensioning a shaft so as to retard the speed of rotation thereof.

One of the objects of the present invention is to provide a tensioning device which willbe capable of exerting any desired degree of pressure vupon the friction drum to offer' more or less resistance to rotation of the shaft with which the device is associated, and which device will conform to the contour of a double conical drum in a manner to most -effectually frictionally coact withV the said drum.

Another object of the invention is to provide an improved form of shoe for the tensioning blocks of such a device which shoe will be more durable and more substantial than the ordinary shoe and perform its functions in a more eective manner.

In the accompanying drawings:

Figure 1 is a perspective view illustrating the tensioning device embodying the invention installed in connection with a printing press; v

Figure 2 is a side elevation of the device installed, the mechanism ofthe press being, however, omitted for the sake of clearness;

yFigure 3 is a perspective view of one of the shoes of the tensioning device removed from its head;

Figure 4 is a transverse sectional view on the line 4-4 of Figure 3.

While the invention is illustrated in the drawings as installed in connection with a printing press vand more specifically with the paper storage roll shaft of the press, the invention is by no means limited to this particular use as it may find embodiment in connection with elevators, hoisting machines, and, in fact, in many types of machines and apparatuses where it is required to place a shaft under tension for one reason or another. In the present instance the paper storage roll shaft is indicated in general by the numeral 1 and is of the ordinary construction and mounted in the usual open bearing 2 from which it may be unseated in 1923. Serial No. 649,984.

applying a new paper roll to the shaft, the purpose of the tensioning device, in this particular embodiment, being to offer suiiicient Vresistance to rotation of the shaft to prevent undue unwinding of the paper through momentum imparted to the shaft in the unwinding of the paper therefrom.

In: the drawings, the numeral l3 indicates a double conical jfri'ctiondrum, the friction surfaces of which are indicated by the numeral 4. The device embodying the invention comprises a i'iXed support 5 which is mounted in any suitable manner 4upon one of the stationary frame members of the press or other machine or mechanism in connectionl with which the device is installed, and pivotally connected to the upper and lower ends of this support are arms 6 which extend one t ing rotatablefor the purpose of rotating the screw to Aeither draw the sleeves 7 toward each other or move them apart. At this point it will be understood that by rotating the hand wheel 10, corresponding motion will be imparted to the screw 9 so as to either draw the arms 6 toward each other about their pivots 11, or move them apart, and it will likewise be understood that the oppositely threaded ends of the screw 9 may bevcompletely disengaged from the sleeves 7 so as to permit of downward swinging movement of the lower arm 6 and an upward and backward swinging movement of the upper arm 6. v y

Each of the arms 6 supports a head which is indicated by the numeral 12, the head, in the construction illustrated in the drawings, being pivotally connected, as at 13, with the respective arm; VThe said heads 12 may be of any desired contour upon their sides which are presented outwardly, but each head has two relatively obliquely disposed and longitudinally arcuate faces indicated by the numeral 14. rIhe relative inclination of the faces 14 and their curvilinear contour, corresponds to the corresponding peripheral contour of the conical surfaces 4 of the friction drum 3. Upon each face 11i of each head there is arranged a shoe the construction of which is best shown in Figures 3 and l of the drawings, the shoe being indicated by the numeral 15. The said shoe 15 is preferably formed from a plurality of plies 16 of heavy leather and they may be united together in any desired manner, being arranged in superimposed relation and the shoe at such time being given the general contour shown in the said Figures 3 and a. Marginally the plies are brought into registration, and the plies are, as stated, united one to another in superimposed relation. lt is preferable that the plies be cemented together so that the shoe, when finished, will constitute a substantially integral block of leather, and the shoe is curved longitudinally and is transversely straight on a diagonal line, each shoe, in fact, being of the shape of a sector of a hollow cone. As a consequence, as illustrated in Figure 1 of the drawings, the friction face of each shoe, indicated by the numeral 18, will engage snugly against and conform to the contour of the respective side of the periphery of the drum 3. Likewise the outer or non-bearing face of each shoe, indicated by the numeral 19, is of a contour to snugly lit against one of the side faces of the respective head 12, and in order that the shoes may be securely held to the faces of the respective heads, a suitable number of the said plies are formed with circular openings 2O which register when the plies are assembled, and a securing screw 21 is fitted through the remaining ply or plies and projects beyond the outer face 19 of the shoe and is threaded into a suitably formed socket in the head 12. rilhus each head 12 supports two of the shoes 15 which shoes are adapted to be brought frictionally into contact with the double conical periph-ery of the friction drum 3,l through rotation of the hand wheel 10, and with a desirable degree of firmness, and the shoes supported by the two heads frictionally bear against the double conicalY periphery of the drum 3 at substantially diametrically opposite points as clearly shown in Figure 2. The degree of pressure exerted by the shoes is regulated by adjusting the wheel 10 to draw the arms 6 toward each other and thus effect the desired gripping action to retard the speed of rotation of the shaft 1. Y

In order that the plies comprising the shoes 15 may be more securely united and prevented from relative displacement, and in order that the shoe as a whole may be rendered more durable, openings 24 are formed through the plies comprising the shoe at points at opposite sides of the opening 20, and wooden plugs 25 of cylindrical form are driven into these openings and are frictionally retained therein. rlhe plugs 25 in themselves constitute friction elements for co-acticn with the periphery of the drum 5, and they, furthermore, serve to materially reinforce the plies comprising the shoe and prevent undue wearing away of the shoe. The plugs being of a material different from that of the leather plies 16, and having their grain running in the direction of their length, will tend to prevent a quick wearing away of' the shoe. lnasmuch as the securing screws 21 have their heads spaced a considerable distance from the friction face 18 of the respective shoes, the shoes may be pern'iitted to wear to a considerable extent before there is any likelihood of the said heads of the screws coming in contact with the friction surfaces 4 of the drum 3. At the saine time the shoes may be readily and quickly renewed whenever occasion requires by rotating the hand wheel 10 until the screw s has disengaged from the sleeves 7, and then permitting the lower arm 6 to drop and swinging the upper arm 6 backwardly, to expose the friction faces of the'shoes.

Having thus describedl the invention, what is claimed as new is:

1. A friction shoe for a tensioning device comprising a block consisting of a plurality of plies of fibrous friction material united together directly face to face, the assemblage of plies being formed with a socket opening through the friction face of the shoe, and a plug of wood fitted into the said socket and presented at one end at the said friction face of the shoe.

2. A friction shoe for a tensioning device comprising a block consisting of a plurality of plies of fibrous friction material united together directly face to face, the assemblage of plies being formed with a socket opening through the friction face of the shoe, a plug of wood fitted into the said socket and presented at one end at the said friction face of the shoe, the grainV of the plug running longitudinally thereof, and attaching means at the opposite face of the block. Y

3. A friction shoe for a tensioning device comprising a block consisting of a plurality of plies of friction material united together, means located substantially centrally of one face of the shoe for securing the same to a supporting part, the shoe at opposite sides of the securing means being provided with sockets, and plugs of wood frictionally held within the sockets and each having an end presented at the friction face of the shoe, the grain of the plugs running longitudinally thereof.

4:. A friction shoe for a tensioning device comprising a block consisting of a plurality of plies of leather directly united together Y face `to face, a socket formed in the assemblage of plies opening through the friction face of the shoe, a plug of fibrous material frictionally held within the socket and having one end presented at the said friction.

face of the shoe, the fibers of the plug being presented endwise at said end thereof, and attaching means at the other face of the block.

5. A friction shoe for a tensioning device comprising a plurality of plies of friction material united together face to face, certain of the plies being formed with registering.

openings forming a recess opening through the friction face of the shoe, and a headed l0 In testimony whereof We affix our signa- 15 tures.r

OSCAR R. GRAF. [n s.] WALTER D. HITCH. [n s] 

